Introduction

Adnexal torsion is a partial or complete twisting of an ovary and/or fallopian tube on its ligamentous supports containing vessels for ovarian blood supply. Torsion may occur in normal ovaries, but occurs more commonly in patients with a pre-existing adnexal mass. US with color Doppler image is established as the initial and choice of study in clinically suspected adnexal torsion. CT or MRI is more objective and helpful, especially in detecting a hemorrhagic component when its presentation is in a subacute condition. Although imaging findings of adnexal torsion may be variable according to the cause of torsion and degree of vascular compromise, the detection of a twisted vascular pedicle or thickened tube is the most speci fic imaging finding of adnexal torsion. CT or MRI findings suggestive of hemorrhagic infarction in adnexal torsion include hemorrhage in the thickened fallopian tube or within the twisted ovarian mass, eccentric smooth wall thickening exceeding 10 mm in a cystic ovarian mass converging on the thickened fallopian tube, peripheral rim enhancement of the twisted pedicle or the mass, or hemoperitoneum.